Currently, blowout preventers (BOPS) are the primary safety device for controlling a well in the case of an unwanted influx of formation fluids entering the well. When a BOP fails, currently the main recourses are to either inject a “junk shot” below the BOP to attempt to plug the flow through the BOP, or drill a relief well to pump in concrete at the base of the well to seal the high pressure region. The junk shot injects (pumps) large quantities of discrete pieces of material (e.g. pieces of rope, balls, etc.) with the intent that some of the materials will hang up on features inside the wellbore and then further bits of junk will build up behind; this approach is difficult because it can suddenly stop the flow and generate a pressure wave that can break the casing, rupture disks, and fracture the formation thus damaging the well and the reservoir. This can result in the entire reservoir being lost through the casing and fractured formation which then could catastrophically leak to the surface over a wide area. Drilling a relief well can take months to complete, during which time the well continues to produce out of control. Therefore, an alternative solution is needed to controllably close off uncontrolled flow through a damaged BOP.